The official death toll climbed to 638 nationwide on Thursday in the Egyptian government’s violent crackdown on protest encampments organized by supporters of deposed President Mohamed Morsi, making it the single deadliest incident since the January 2011 revolution that ended the dictatorship of President Hosni Mubarak. Egypt’s Health Ministry added that there were at least 3,717 injured, and casualty figures are expected to climb. The Interior Ministry separately announced that 43 security personnel died in the violence.

The deaths have cast a pall over Egypt, which is in the grips of a political crisis no less intense than the original upheavals that unseated Mubarak. According to government figures, 846 people were killed during the 18 days of the pro-democracy revolution in 2011. Yesterday’s crackdown ended over a month in which Morsi’s supporters had doggedly camped out in public squares, demanding his reinstatement. Egypt’s military had removed Morsi, an official in the Muslim Brotherhood who had won Egypt’s presidential election in 2012, from power on July 3 after a major wave of street protests over his handling of the economy and for failing to govern inclusively.

The largest number of fatalities, at least 137 according to a Health Ministry spokesman quoted by the government-owned Al-Ahram news website, took place when security forces backed by bulldozers and helicopters forcibly dispersed a sit-in that had grown to the size of a village in Rabaa Adaweya Square, in the suburban Cairo neighborhood of Nasr City. At the nearby Al-Iman Mosque, where many of the bodies were taken, it was clear that Egypt’s political convulsions were entering an even darker, more violent phase.

At the doors of the mosque, hundreds of onlookers and members of bereaved families jostled to get inside. One man stood solemnly in the crowd with a half-burned copy of a Koran he said he had recovered from the camp.

The door periodically burst open and volunteers inside struggled to keep the crowds at bay, spraying air freshener — used within to mask the stench of death — in the eyes of people trying to enter. A group of men stood at the door, sweating and perplexed. One was trying to deliver ice to preserve the bodies. Another carried paperwork that he said permitted him to enter.

The door opened again. Men carrying a coffin emerged. The crowd shouted “Allahu akbar!” (God is Great!) Then the doors slammed shut.

The door would open again and again, every few minutes, each time a new body emerging, each time triggering new chants of “Allahu akbar!” One small body, perhaps belonging to a child or teenager, also came through the door, wrapped in a sheet.

Inside the mosque, the scene was calmer. A man read the names of the dead over a loudspeaker. Family members sat with the corpses of their loved ones, wrapped in white sheets, packed in ice. Some of the bodies were burned beyond recognition. Some were missing limbs. Others’ skulls had been crushed.

Back outside, some of the protesters displaced from the Rabaa sit-in lingered in the courtyard, not knowing what to do next. The interim military-backed government has declared a monthlong state of emergency and imposed an all-night curfew in the capital and 10 other provinces. Cairo’s usual gridlock traffic was nowhere to be found on Thursday, and the number of cars on downtown Cairo’s streets dwindled even further as the 7 p.m. curfew approached.

Muhammad Azmi Mustafa, 28, an imam from a Cairo mosque, said he had visited the encampment nearly every day for a month, and had been present when the crackdown began. He described a ferocious scene of security forces attacking by both land and air, firing bullets and tear gas.

When asked what direction the pro-Morsi movement will now take, Mustafa demurs. “The decision is the martyrs’ families’ now. It’s not up to us,” he says. But he was certain of one thing. “Peaceful protest is dead now.”